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/*
* linux/fs/msdos/dir.c
*
* Written 1992,1993 by Werner Almesberger
*
* MS-DOS directory handling functions
*/
#include <asm/segment.h>
#include <linux/fs.h>
#include <linux/msdos_fs.h>
#include <linux/errno.h>
#include <linux/stat.h>
static int msdos_dir_read(struct inode * inode,struct file * filp, char * buf,int count)
{
return -EISDIR;
}
static int msdos_readdir(struct inode *inode,struct file *filp,
struct dirent *dirent,int count);
static struct file_operations msdos_dir_operations = {
NULL, /* lseek - default */
msdos_dir_read, /* read */
NULL, /* write - bad */
msdos_readdir, /* readdir */
NULL, /* select - default */
NULL, /* ioctl - default */
NULL, /* mmap */
NULL, /* no special open code */
NULL, /* no special release code */
file_fsync /* fsync */
};
struct inode_operations msdos_dir_inode_operations = {
&msdos_dir_operations, /* default directory file-ops */
msdos_create, /* create */
msdos_lookup, /* lookup */
NULL, /* link */
msdos_unlink, /* unlink */
NULL, /* symlink */
msdos_mkdir, /* mkdir */
msdos_rmdir, /* rmdir */
NULL, /* mknod */
msdos_rename, /* rename */
NULL, /* readlink */
NULL, /* follow_link */
msdos_bmap, /* bmap */
NULL, /* truncate */
NULL /* permission */
};
static int msdos_readdir(struct inode *inode,struct file *filp,
struct dirent *dirent,int count)
{
int ino,i,i2,last;
char c,*walk;
struct buffer_head *bh;
struct msdos_dir_entry *de;
if (!inode || !S_ISDIR(inode->i_mode)) return -EBADF;
if (inode->i_ino == MSDOS_ROOT_INO) {
/* Fake . and .. for the root directory. */
if (filp->f_pos == 2) filp->f_pos = 0;
else if (filp->f_pos < 2) {
walk = filp->f_pos++ ? ".." : ".";
for (i = 0; *walk; walk++)
put_fs_byte(*walk,dirent->d_name+i++);
put_fs_long(MSDOS_ROOT_INO,&dirent->d_ino);
put_fs_byte(0,dirent->d_name+i);
put_fs_word(i,&dirent->d_reclen);
return i;
}
}
if (filp->f_pos & (sizeof(struct msdos_dir_entry)-1)) return -ENOENT;
bh = NULL;
while ((ino = msdos_get_entry(inode,&filp->f_pos,&bh,&de)) > -1) {
if (!IS_FREE(de->name) && !(de->attr & ATTR_VOLUME)) {
for (i = last = 0; i < 8; i++) {
if (!(c = de->name[i])) break;
if (c >= 'A' && c <= 'Z') c += 32;
if (c != ' ') last = i+1;
put_fs_byte(c,i+dirent->d_name);
}
i = last;
put_fs_byte('.',i+dirent->d_name);
i++;
for (i2 = 0; i2 < 3; i2++) {
if (!(c = de->ext[i2])) break;
if (c >= 'A' && c <= 'Z') c += 32;
if (c != ' ') last = i+1;
put_fs_byte(c,i+dirent->d_name);
i++;
}
if ((i = last) != 0) {
if (!strcmp(de->name,MSDOS_DOT))
ino = inode->i_ino;
else if (!strcmp(de->name,MSDOS_DOTDOT))
ino = msdos_parent_ino(inode,0);
put_fs_long(ino,&dirent->d_ino);
put_fs_byte(0,i+dirent->d_name);
put_fs_word(i,&dirent->d_reclen);
brelse(bh);
return i;
}
}
}
if (bh) brelse(bh);
return 0;
}